How do you reach the biggest TV audience of the year, half of whom are already tuning in just for the commercials, and get them to focus on the ads even more?

Do you let the public choose the ending, as Coca-Cola has done with their "chase" spot, urging fans to log onto CokeChase.com and decide if Las Vegas showgirls, hard-riding cowboys or Mad Max-style "badlanders" will win a race through the desert on Super Bowl night?

Do you ask fans to send in photos, as Pepsi has done for its spot just before R&B diva Beyonce's half time show? (Though many photos will appear in the ad, 50 lucky winners will participate in the halftime show.)

Do you have fans answer questions over Twitter and use their responses to build an ad, as late-night host Jimmy Fallon did with his 7.6 million followers for a campaign bankrolled by Ford's Lincoln auto line dubbed #Steerthescript?

Do you release the full spot — or an even longer version — well in advance to assure lots of appearances in social media and news stories, as Mercedes, Audi and Volkswagen did?

(The downside there: Critics can pick apart unorthodox spots before game time, as Volkswagen discovered when its spot featuring a lighthearted white Minnesotan speaking with a Jamaican accent sparked concerns of racism and Arab groups objected to a man shown in Coke's "Chase" commercial.)

With more than 100 million viewers expected this year, marketers have tried a wide array of social media experiments, smartphone goodies and contests aimed at making the most-watched commercials of year an even bigger event.

According to the Associated Press, about half of the 30 marketers running Super Bowl ads have already released teaser trailers, partial clips or full versions of their spots.

And after some time spent trolling YouTube, Hulu and the wilds of social media, here are this critic's picks for the ones to watch.

Best fan choice. Audi fans nailed their Super Bowl ad choice this year, picking "Prom," a commercial where a nerdy kid drives his dad's luxury car to the big dance alone, kisses the pretty girl and gets a shiner for his trouble. Trust me. Despite the ending, it's still cute.

Best use of kids/babies. It's a longstanding rule of Super Bowl ads that kids, animals, sex and celebrities rule (excepting perhaps the super-played out E*trade baby). So it's no surprise Kia's "Space Babies" ad, where a dad tells his young son that infants come from a distant planet, has produced the coolest visual so far; a spacesuit-wearing youngster striding along a space capsule catwalk like Neil Armstrong.

Best use of senior citizens since Cocoon. Loved Taco Bell's "Viva Young" video, featuring a gang of seniors sneaking out of their rest homes to tear up the town like younger, hard-partying fast food fans (though watching a 60something getting "Goldblatt" tattooed across his back pushed the bounds of taste a bit for me). Extra points for setting it all to a Spanish-language version of Fun.'s We Are Young.

Best Anthony Sullivan spoof. Tide pulls off a cheeky infomercial parody for "stain saver" stickers you can place on shirts, using a host whose British tones sound suspiciously like Tampa-based TV pitchman Sullivan.

Best ad we haven't seen yet. For me, this is a tossup between two Saturday Night Live alums expected to appear during the Big Game. Parks and Recreation star Amy Poehler will stand up for Best Buy in a 30-second spot, while 30 Rock co-star Tracy Morgan appears for its "liquid water enhancer" Mio.

If either spot is half as funny as Poehler's turn co-hosting the Golden Globes or Morgan's surprise shtick at the Emmys, we're in for a treat.